Diverse multi-organ histopathologic changes in a failed Fontan patient.

We report multi-organ histopathological changes in a patient with protein-losing enteropathy (PLE) over 12 years after Fontan operation. A 14-year-old boy with right isomerism heart and single ventricle had undergone Fontan procedure at 19 months of age, and PLE was diagnosed at 28 months. He had several episodes of intestinal bleeding and pre-renal failure with elevated creatine, and eventually died of pneumonia. The intrapulmonary small arteries showed medial and intimal thickening resembling pulmonary hypertension. No major ulcerative lesions were found in the small or large intestines. Dilated lymph ducts, one of the characteristic features of PLE, were not seen in mucosal and submucosal areas. Liver cirrhosis was obvious despite little increase in liver enzymes. Histological changes in bilateral kidneys were subtle despite repeated episodes of renal failure. Thus, there may be significant discrepancies between clinical manifestations and multi-organ histological changes in failed Fontan patients.